The museum is located in the family mansion of Count Negroni that was built in 1925. It was opened to the public in 1946. The origins of the museum date back to the late 19th century when the natural sciences were developing; the period was marked by a growth in the research and scientific interest in the sea around the Kvarner area and the emergence of numerous private collections.

The Natural History Museum of Rijeka acts as a scientific and educational institution, and is the only institution dealing with the biological and ecological study of the sea in Primorje-Gorski Kotar County. It works intensively on popularising the natural sciences.

The museum manages 29 collections, which hold approximately 90,000 artifacts.
The arrangement of the permanent display by topic began in 1998, accompanied by the introduction of new information technologies.

One of the most impressive displays is Sharks and Rays, which displaystaxidermied fish in dioramas of their natural habitat, accompanied by a multimedia presentation (photographs, images, and video sequences).

The permanent exhibition Geological History of the Adriatic shows the genesis and development of the Adriatic Sea basin, while Geology of the Rijeka Region is devoted to local geological development.

The ground floor of the museum features an aquarium multimedia centre that includes a workshop/play area with educational games based on natural history, as well as a gallery for temporary exhibitions.

The displays Birds and Mammals of the Rijeka Region and Reptiles and Amphibians of the Rijeka Region are presented in dioramas. The display Insects of the Rijeka Region is yet another curiosity of this museum.

All exhibitions include CDs or DVD-ROMs with natural science content. Also included are educational games and quizzes to test knowledge.

There is a Coastal Botanical Garden in the vicinity of the museum that was cultivated in 2005, which features the most common plant species in this region. The Botanical Garden also provides educational activities and a space for visitors to relax.